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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 2 |
| 3 | 6 |
| 4 | 8 |
| 5 | 23 |
| 6 | 60 |
| 7 | 149 |
| 8 | 396 |
| 9 | 1050 |
| 10 | 2814 |
| 11 | 7571 |
| 12 | 20372 |
| 13 | 54879 |
| 14 | 147946 |
| 15 | 399002 |
| 16 | 1076312 |
| 17 | 2903613 |
| 18 | 7833652 |
| 19 | 21135287 |
| 20 | 57024772 |
| 21 | 153859830 |
| 22 | 415135862 |
| 23 | 1120101045 |
| 24 | 3022215348 |
| 25 | 8154444873 |
| 26 | 22002086130 |
| 27 | 59365425382 |
| 28 | 160178219728 |
| 29 | 432188727639 |
[1,2,6,8,23,60,149,396,1050,2814,7571,20372,54879, 147946,399002,1076312,2903613,7833652,21135287, 57024772,153859830,415135862,1120101045, 3022215348,8154444873,22002086130,59365425382, 160178219728,432188727639] |